split out config parsing into its own crate

Cargo.lock

Cargo.toml

src/config/nc.rs

tests/configs/basic.php

tests/configs/comment_whitespace.php

tests/configs/empty_redis_password.php

tests/configs/full_redis.php

tests/configs/implicit_prefix.php

tests/configs/multiple/config.php

tests/configs/multiple/db.config.php

tests/configs/mysql_fqdn.php

tests/configs/port_in_host.php

tests/configs/postgres_socket.php

tests/configs/postgres_socket_folder.php

tests/configs/redis.cluster.php

tests/configs/redis_socket.php